Podcaster: Dr. Al Grauer


Title: Travelers in the Night Eps. 189E & 190E: Frequent Visitor & Martian Purity

Organization: Travelers in The Night

Link : Travelers in the Night ; @Nmcanopus

Description: Today’s two stroy:

  • Rose Matheny discovered 2015 UM52
  • Lichen from atop the Black Ridge in Antarctic’s North Victoria Land could flourish in Mars-like conditions provided that it is shielded from most of the ultraviolet radiation from the Sun.

Bio: Dr. Al Grauer is currently an observing member of the Catalina Sky Survey Team at the University of Arizona.  This group has discovered nearly half of the Earth approaching objects known to exist. He received a PhD in Physics in 1971 and has been an observational Astronomer for 43 years. He retired as a University Professor after 39 years of interacting with students. He has conducted research projects using telescopes in Arizona, Chile, Australia, Hawaii, Louisiana, and Georgia with funding from NSF and NASA.

He is noted as Co-discoverer of comet P/2010 TO20 Linear-Grauer, Discoverer of comet C/2009 U5 Grauer and has asteroid 18871 Grauer named for him.

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189E: Frequent Visitor

In 1933 an asteroid about the size of a large U-Haul moving truck went unnoticed as it passed within about 5 times the Earth’s circumference from the surface of our planet.   During the next 82 years this space rock came close to Earth 13 times without humans being aware of its existence.  In 2015 this object approached the Earth at 5 miles/second from the nearly the direction of the Sun.  On its approach to Earth, it got 100 times brighter in 5hr, as more of its lighted side faced towards us.  At its closest point to Earth it was about 8 times the distance from New York to Sydney.  Thirty six hours later my Catalina Sky Survey teammate Rose Matheny discovered it moving away from Earth at 5 miles/second. By then it was already 630,000 miles from her.  After Rose submitted her observations to the Minor Planet Center it was tracked by telescopes in Arizona, Texas, Wisconsin, and Japan.  The Minor Planet Center used these data to calculate and orbit and gave it the name 2015 UM52.

2015 UM52 orbits the Sun once every 610 days on a path which goes from inside of our orbit to a bit past Mars.  Its orbit allows it to eventually pass within 3 Earth diameters of the surface of our home planet.  2015 UM52 will not come anywhere near that close to us as it makes 11 visits to our vicinity in the next 125 years. 

190E: Martian Purity

The NASA/JPL Curiosity Rover was sent to Mars to explore and to look for evidence of ancient life on what we thought was likely to be a dry, dead planet.  In its directed rambling Curiosity has discovered undeniable evidence that Mars once had lakes, rivers, and oceans of liquid water.  

But what about the present?  Recently, orbiters circling the red planet have taken images which show football field length channels. These features change with the Martian seasons and appear to be the result of present day flows of salty water in at least a dozen places on the red planet.  Could these briney springs be the home of living Martian organisms? To find out humans had better be extremely careful not to introduce any of Earth’s life forms into these places.

Recent scientific research shows that lichen from atop the Black Ridge in Antarctic’s North Victoria Land

will flourish in Mars like conditions provided that it is shielded from most of the ultraviolet radiation from the Sun.

All of this has caused scientists to wonder if one of Earth’s toughest creatures could have possibly hitchhiked a ride to Mars on the Curiosity Rover’s belly.  If so we we would not want to give these hardy survivors a chance to take over one of Mars’s salty springs.  At least for now Curiosity will be banned from these sensitive areas.  In the future our robotic emissaries to the red planet will need to be completely sterilized if we are to be sure that any organisms we discover are purely Martian.

End of podcast:

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